Marine salvage apparatus

ABSTRACT

A ship hull is divided into a pair of tanks, the first being centrally disposed of the hull and the second disposed peripherally of the first. The tanks are movable upwardly and downwardly independently one of the other in response to variations in the buoyancy of each tank. Positive buoyancy is employed to raise the load. For this purpose, each tank is secured to the load by a winch-operated cable and each tank forms a part of the skin surface of the ship so as to be exposed to the buoyancy forces. A motor-driven pump permits the filling and evacuating of each tank, the lifting force being achieved by initially tightening all of the cables, submerging one of the tanks to slacken its cable which then again may be tightened with this tank in its submerged disposition. Sea water than is pumped from this submerged tank to create a positive buoyancy which, due to the tightened cable, lifts the load. Next the other tank is submerged to produce a slack in its cable while the cable of the previously-submerged tank remains taut. Slack is again taken up and the submerged tank pumped to provide another incremental lifting force. Successive incremental lifting forces raise the object to the surface. The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

United States Patent lnventor Appl. No.

Filed Patented Assignee John J Bayles Oxnard, Calif.

Aug. 8, 1969 Mar. 2, 1971 the United States of America as represented by the Secretary of the Navy MARINE SALVAGE APPARATUS 50, 51,5 2, 46, 45, 48, 53; 61/65, 69 (R) References Cited UNITED STATES PATENTS 1,288,108 12/1918 Messer 6/1934 McArdleeta Primary ExaminerMi1ton Buchler I Assistant ExaminerGregory W. OConnor Attorneys-R1. Tompkins and Paul N. Critchlow ABSTRACT: A ship hull is divided into a pair of tanks, the first being centrally disposed of the hull and the second disposed peripherally of the first. The tanks are movable upwardly and downwardly independently one of the other in response to variations in the buoyancy of each tank. Positive buoyancy is employed to raise the load. For this purpose, each tank is secured to the load by a winch-operated cable and each tank forms a part of the skin surface of the ship so as to be exposed to the buoyancy forces. A motor-driven pump permits the filling and evacuating of each tank, the lifting force being achieved by initially tightening all of the cables, submerging one of the tanks to slacken its cable which then again may be tightened with this tank in its submerged disposition. Sea water then is pumped from this submerged tank to create a positive buoyancy which, due to the tightened cable, lifts the load. Next the other tank is submerged to produce a slack in its cable while the cable of the previously-submerged tank remains taut. Slack is again taken up and the submerged tank pumped to provide another incremental lifting force. Successive incremental lifting forces raise the object to the surface.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

m l6 l7 PATENTED "AR 2 I9" INVENTOR. JOHN J. 84 YL E5 ATTORNEY MARINE SALVAGE APPARATUS BACKGROUND OF THE INVENTION The present invention relates to marine salvage systems and, in particular, to salvage operations conducted from a floating vessel having lengthy cables stretching to and secured to the object to be salvaged.

Marine salvage operations always have been a vital concern at least for as long as there have been disasters at sea in which the cargo or the craft has been of sufficient value to warrant retrieval= and, as would be expected, this concern has produced a'variety of widely-varying proposals some of which involve the use of buoyancy chambers filled with air or low dnsity' material or the use of mechanical winches and other means to power the loads up to the surface. In the early days salvage was restricted to very shallow depths at which divers could operate but, as technology developed and greater depths became accessible the accompanying. need arose for systems capable of operating at these depths. Again a variety of proposals were forthcoming. However, for one reason or another, the presently-available systems do not appear to provide the efficiency or speed of operation needed for the job. For example, it is desirable to provide a salvage ship capable of transporting the salvage apparatus to the scene of operations and, in this regard, some of the proposals utilize a relatively awkward arrangement in which a variety of equipment must be separately carried to the scene for assembly and use. Also, it is desirable in these salvage operations to have a system in the form of a ship hull which is capable of raising the sunken object a certain distance off of the bottom and then proceeding toward a port or a protected location with the object partially raised. Again, salvaging equipment formed of separate units usually requires completely raising the object to the surface before it can be transported.

Aside from such functional aspects of the operation, many other considerations must be taken into account before the expense of worldwide salvaging systems can be justified. Some systems, for example, may be feasible but the expense which may include either the power arrangement or the size of a vessel, have proven prohibitive.

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide marine salvage apparatus capable of being carried by a ship to and from the salvage operation site.

Another object related to the foregoing object is to provide apparatus capable of partially raising the load to permit transport of the load in the partially raised disposition.

A further object is to provide a marine salvage system according to the previous objects, the apparatus of the system being relatively inexpensive, low-powered and easily and quickly placed into operation.

Another important object which also constitutes one of the significant features of the present invention is to provide salvage apparatus capable of utilizing the normal buoyancy force on a ship hull as the lifting force for the salvage operatron.

These and other objects, which will become more apparent in the ensuing description, are achieved primarily by providing ship hull which, of course, has a water-planing skin portion that is hydrodynamically shaped to facilitate underway travel of the ship. The hull mounts a pair of tanks and each tank has a wall section which generally, during the underway travel, forms a part of the water-planing skin portion of the ship hull. Pump means are utilized for separately filling each tank with water and for evacuating the water to permit the buoyancy of each tank to be independently varied. The tanks, most suitably, are disposed one next to the other and, in a preferred form, there is a'first central tank about which is a peripheral or hull tank, the two tanks together forming essentially the entire hull portion of the ship. Also, the tanks are independently movable in response to their buoyancy variations, the movaelevated relative to its normal underway disposition. As a practical matter each tank should have adequate internal.

capacity to provide an elevating buoyancy force sufiicient to lift the load. A lifting cable secures each tank to the load andwinch means or the like are provided for lowering the cables.

f r engagement with the load and for independently tightening each engaged cable. The hoisting operation is achieved by first tightly securing the cables to the'load following which one of the tanks is submerged to slacken itscable while the other cable tautly supports the load. The slackened cable then is tightened and its tank evacuated in a controlled manner to provide the positive buoyancy force requiredto partially lift the load. Next, the other tank is partially submerged, itscable tightened and its interior evacuated to provide another-lift increment for the load. As soon as the load is lifted sufficiently to clear bottom ridges or the like, the ship can be put underway to transport the load to its destination or to a relatively. calm location at which the hoisting operation can be completed. Of course, the load also can be lifted into a disposition directly beneath the ship hull at its salvage site.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is schematically illustrated in the accompanying drawings of which FIG. 1 is a plan view of the ship hull I showing the tanks in outline and also schematically illustrating a winch system as well as a pumping system for adjusting the buoyancy of the tanks;

FIG. 2 is a sectional view taken along lines lI-II of FIG. 3; and

FIGS. 3-8 are schematics illustrating the manner in which the present apparatus lifts a load such as a submarine.

DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, the present salvage apparatus is an integrated part of a ship hull 1 which, as shown in other FIGS. is hydrodynamically shaped to facilitate the usual underway travel of a ship. lt-is contemplated that the ship may have its own propulsion means which may be mounted in any suitable manner, although it may be found less expensive and easier simply to utilize the present ship as a tow which can be transported to and from the salvage operation site by other available powered vessels.

As stated, the ship carries or mounts the present salvage system but, more precisely and in a manner which will become apparent, the present salvage system, in effect, constitutes essentially the entire ship. Thus, as shown in FIG. 1 and other FIGS. the entire ship is divided into a pair of tanks 2 and 3, tank 2 being a centrally disposed tank while tank 3 is disposed peripherally about tank 2, both tanks together utilizing almost the entire hull capacity of the ship. These tanks are disposed closely adjacent one another and, for present purposes, must be capable of moving independently ofone another to the extent that any variation in the buoyancy of either tank permits it to rise or fallwith respect to the other tank. Most suitably,

the tanks are provided with a slidable interconnection which may be formed in any suitable manner suchas the slot and key interconnection illustrated in FIG. 2. Such an interconnection is capable of guiding or controlling the rising or falling movements of the tanks.

As just indicated, it is intended that the tanks rise and fall in response to buoyancy variations and these variations, of course, are achieved by filling the tanks with sea water or evacuating the sea water to produce a more positive buoyancy. First, however, it is important to note that each of the tanks has a wall portion designated in FIG. 3 by numerals 2a and 311, these portions forming a part of the skin surface of the ship hull which is exposed to sea water when the ship is afloat.

The buoyancy of the sea water acts on the surfaces 20 and 3a to produce the rise and fall of the tanks as they are filled or emptied. The fillingor emptying of the tanks can be achieved in different manners to the extent that each of the tanks canbe filled directly from the sea water or the tanks can be initially filled and the water then pumped from one tank to the other. A motor driven pump 4 may be utilized for this purpose. As schematically illustrated in FIG. 1, this pump is communicated with the sea water by means of a conduit 6 and also communicated with the tanks by conduits 7 and 8. Valves 9 are disposed in the conduits to permit the selection of a desired mode of operation. Thus, the valves may be opened or closed to permit the pumping of sea water directly into either or both of the tanks, or valve 9 of conduit 6 can be closed and the other valves adjusted to permit pumping of the sea water from one tank into the other. It also should be noted that some saving in power can be obtained by utilizing remotely controlled valves 10, shown in FIG. 3, to admit sea water directly into the tanks without the need for pumping. For example, when an empty tank is in a slightly submerged position the opening of its valve 10 will permit an initial flow of sea water into the tank and avoid the necessity of pumping that particular amount of water.

Other features of the invention can be understood with reference to the functional schematics of FIGS. 3-8. In FIG. 3, for example, the ship is illustrated in its normal position in which the tanks are at the same level to provide an arcuate hydrodynamic hull form to facilitate underway travel. Most suitably, special means, such as latches 11 shown in FIG. 1, are provided to maintain the tanks in this leveled disposition. Latches 11 are shown schematically and may assume any desired form. As shown, they include a cleat 12 and a swingable latch arm 13 which can be moved beneath the cleat and preferably biased into a locked position to lock the tanks together and prevent undesired movement while underway.

In FIG. 3 the ship which, in effect, is salvage system, is shown stationed above an object such as submarine 14 which is to be salvaged. Each tank 2 and 3 mounts a pair of winches 16 and 17, preferably in fore-and-aft positions, and each winch controls a cable identified as cables 18 and 19 which are secured in any suitable manner to the submarine to be salvaged. It is recognized that difficulties are experienced in securing cables to sunken objects when the objects are at great depths. However, the advent of deep submersibles with remotely controlled, articulated arms can be employed for this purpose and it is known that other feasible suggestions have been made to tunnel beneath a sunken submarine and permit the submarine to be secured in what amounts to a sling arrangement.

The initial step in a salvage operation is to tighten both cables 18 and 19 in the manner illustrated in FIG. 3. It also will be noted that in FIG. 3 tanks 2 and 3 contain a certain level of sea water which either can be normally present as underway ballast or can be admitted through valves 10 after the ship is in salvage position. With the cables so secured and tightened, sea water is pumped from tank 3 into tank 2 to produce a negative buoyancy in tank 2 and cause it to sink into the position shown in FIG. 4, this sunken condition producing a slack in cable 19.

The next step, as illustrated in FIG. 5, is to tighten cables 19 and, following the tightening of these cables, to commence pumping sea water from tank 2 into peripheral or hull tank 3. As shown, this pumping produces a positive buoyancy force to lift submarine 14.

In FIG. 6, central tank 2 has been completely evacuated so that it has been raised essentially to sea level and submarine 14 also raised an increment equal to the rise of the tank. Peripheral tank 3 has been further depressed to produce a greater slack in cables 18 which next, as shown in FIG. 7, are drawn taut by their winches 16.

The final step in this progression of steps is indicated in FIG. 8 in which sea water has been pumped from peripheral tank 3 into central tank 2, the pumping of the sea water producing a positive buoyancy in the peripheral tank which also produces another incremental lift for submarine 14. Although not illustrated, continued pumping of the sea water from tank 3 into tank 2 will cause the peripheral tank to rise essentially to sea level and the submarine, of course, to be lifted even further.

Obviously it is not necessary to completely empty or fill each tank and it is expected that optimum procedures will be established for each operation.

If it is desired to raise the submarine completely to the surface or rather to a position directly beneath the salvage ship, the series of steps just outlined can be repeated to the required extent. However, in many instances, it is more desirable to transport the submarine from the salvage site into more protected waters or possibly to a port area without completely lifting it into a position beneath the salvage ship. If such is desired, the level of sea water in both tanks 2 and 3 can be adjusted to bring the tanks into the relative disposition illustrated in FIG. 3 and the ship can be driven or towed to the desired protected location. During such underway travel, the tanks would be locked in their FIG. 3 position and the cables, of course, tightened.

The present salvage system is considered to be a practical means for raising extremely heavy loads from deep water depths. In particular, it is intended to be used as a ship salvage system. Its advantages include the fact that peak power requirements for the system are greatly reduced since the winches are required only for the purpose of taking up slack line and they are not required to power-up the heavy load. The load is raised by buoyancy created by pumping water from one chamber to the other, although as has been indicated, it is equally feasible to pump the water directly from the ocean into the tanks rather than from one tank into the other. As a further saving in power, it is anticipated that during a portion of each cycle the water in one chamber can be free flooded into the other. A further significant advantage of the present system is its ability to be driven or towed as a unit to the site where it is capable of raising the sunken ship sufficiently to permit transport of the sunken ship in a cable-suspended position to a protected area or to a port. In many of the suggested operations presently under consideration, this transport cannot be accomplished until the lift phase is complete and this fact may expose the whole salvage operation precariously to the mercy and whims of nature.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

Iclaim:

1. Apparatus for lifting large and heavy loads from deep ocean depths comprising:

a ship hull having a water-planing skin portion normally providing a continuous arcuate surface facilitating underway travel of the ship;

a pair of tanks each having a wall section normally forming part of said skin portion;

pump means for separately filling each tank with water and for evacuating the water whereby the buoyancy of each tank can be independently varied;

said tanks each being independently movable in response to said buoyancy variations permitting the tank to be partially submerged and elevated relative to its normal underway disposition, and each tank having sufficient internal capacity to provide an elevating buoyancy force sufficient to lift said load;

a lifting cable for each tank;

winch means for lowering the cables for engagement with said load and for tightening each engaged cable independently of the other; and

whereby when both of said cables are tautly secured to the load one of said tanks can be submerged to slacken its cable while the other cable tautly supports the load thus enabling the load to be incrementally lifted by alternately tightening each slackened cable and evacuating its tank, the evacuation buoyantly elevating the tanks and the load.

2. The apparatus of claim 1 further including means for maintaining said pair of tanks in said normal underway disposition. Y

the load during said incremental lifting actions.

5. The apparatus of claim 3 wherein said tanks slidably engage one another for mutually guiding said independent submersion and elevation movements.

6. The apparatus of claim 3 wherein the water-planing surface of each tank is provided with a remotely-controlled part for selectively admitting water into the tanks. 

1. Apparatus for lifting large and heavy loads from deep ocean depths comprising: a ship hull having a water-planing skin portion normally providing a continuous arcuate surface facilitating underway travel of the ship; a pair of tanks each having a wall section normally forming part of said skin portion; pump means for separately filling each tank with water and for evacuating the water whereby the buoyancy of each tank can be independently varied; said tanks each being independently movable in response to said buoyancy variations permitting the tank to be partially submerged and elevated relative to its normal underway disposition, and each tank having sufficient internal capacity to provide an elevating buoyancy force sufficient to lift said load; a lifting cable for each tank; winch means for lowering the cables for engagement with said load and for tightening each engaged cable independently of the other; and whereby when both of said cables are tautly secured to the load one of said tanks can be submerged to slacken its cable while the other cable tautly supports the load thus enabling the load to be incrementally lifted by alternately tightening each slackened cable and evacuating its tank, the evacuation buoyantly elevating the tanks and the load.
 2. The apparatus of claim 1 further including means for maintaining said pair of tanks in said normal underway disposition.
 3. The apparatus of claim 1 wherein one of said pair of tanks is disposed centrally of the hull and the other disposed adjacent to and peripherally of said center tank, said pair of tanks providing essentially the entire water-planing skin portion of the hull.
 4. The apparatus of claim 3 wherein said tanks each have a pair of cables spaced in a fore-and-aft direction relative to the hull for providing at least a two-point balanced suspension of the load during said incremental lifting actions.
 5. The apparatus of claim 3 wherein said tanks slidably engage one another for mutually guiding said independent submersion and elevation movements.
 6. The apparatus of claim 3 wherein the water-planing surface of each tank is provided with a remotely-controlled part for selectively admitting water into the tanks. 